Certain known wind power turbines used to produce electric energy include a blade assembly and an electric generator, which transforms part of the kinetic energy from the blade assembly into electric energy, and dissipates the rest in the form of heat, which must be disposed of for the electric generator to operate efficiently.
The electric energy produced is subsequently phase and frequency transformed in static electric machines, which are cooled to improve performance.
The wind power turbines described in U.S. Pat. No. 7,057,305, U.S. Pat. No. 7,161,260, U.S. Pat. No. 6,676,122, U.S. Pat. No. 7,594,800, and EP Patent No 2,136,077 therefore comprise respective air cooling systems. More specifically, EP Patent No. 2,136,077 describes a tubular electric generator air cooling system in which a stream of air is forced successively through the hub, the tubular electric generator, and the nacelle. In other words, air flows in through a first opening in the hub, and out through a second opening in the rear of the nacelle.
Certain known air cooling systems provide for fairly good performance of wind power turbine electric machines and generators installed in relatively mild or cold climates.
In very hot climates, however, liquid cooling systems must be used.
For example, U.S. Pat. No. 7,168,251 B1 describes a wind power turbine comprising a closed-circuit cooling system using a liquid cooling medium.
Wind power turbines must often be designed and built with cooling systems designed according to the climate of the proposed turbine installation site (i.e., capable of achieving maximum power and efficiency of the electric machines as a function of the climate in which the turbine is installed).
Designing and building wind power turbines according to the climate of the installation site seriously reduces turbine component part standardization and mass production saving.
Moreover, in connection with the above, known cooling systems are not even particularly versatile or effective in cooling the electric generator.